Gas turbine engines are used to power aircraft, watercraft, power generators, and the like. Gas turbine engines typically include a compressor, a combustor, and a turbine. The compressor compresses air drawn into the engine and delivers high pressure air to the combustor. In the combustor, fuel is mixed with the high pressure air and is ignited. Products of the combustion reaction in the combustor are directed into the turbine where work is extracted to drive the compressor and, sometimes, a fan to generate thrust to propel the aircraft. Left-over products of the combustion are exhausted out of the turbine and may provide additional thrust in some applications.
In some propeller driven aircraft, the propeller blades are configured to pivot about their respective axis to vary a pitch of the propeller blades. The pitch of the blades may be controlled using actuators and/or counterweights coupled directly to the propeller blades. However, such control methods may be limited by design space and weight allocations when incorporated into fans used with gas turbine engines.